1. Field
The present disclosure relates generally to platforms with rotating structures and, in particular, to a method and apparatus for transferring signals between a rotating structure and a non-rotating structure.
2. Background
Many types of platforms have structures that rotate relative to each other. These types of structures are found in various platforms, such as unmanned aircraft, manned aircraft, missiles, spacecraft, miniature robotics, ships, satellites, space stations, and other types of platforms.
With these types of platforms, signals may be transmitted between a rotating structure and a non-rotating structure on the platform. These signals may take the form of power and/or data. The signals may be optical and/or electrical. For example, a satellite may have a dish antenna. The dish antenna may be maintained in a stationary position relative to the earth, while the satellite may rotate. As another example, a robot may have a robotic arm that rotates.
Various mechanisms are used to provide connections to send signals between these types of structures. For example, slip rings, pre-twisted wire bundles, flexible tape cables, and mercury-filled rotary devices have been used to transmit signals between a rotating structure and a non-rotating structure.
With aircraft, spacecraft, and other similar vehicles, the size, shape, and weight of these types of structures may influence the performance of the vehicles. Reductions in the size of various structures are desirable because the reductions may result in decreased weight and volume. Additionally, these reductions also may provide a capability to reduce the number of structural components needed to support a rotating structure and a non-rotating structure with respect to each other. The reductions in structures may occur as the size of various devices and electronics in a platform decrease.
Many of the currently available mechanisms for transmitting signals between these types of structures, however, do not provide the desired amount of rotation. Further, as these structures decrease in size, mechanisms, such as flexible tape cables, rotary joints, pre-twisted wire bundles, and mercury-filled rotary devices may limit the design of structures because of the space requirements for these devices.
Therefore, it would be advantageous to have a method and apparatus that takes into account at least some of the issues discussed above, as well as possibly other issues.